Consider supporting redirects file or similar

[untitaker]

Netlify has a very simple file format for redirects: https://docs.netlify.com/routing/redirects/

I wonder if hyperlink should honor that file. But I imagine that for the purposes of link-checking, one could also do this:

cat _redirects | while read _from _to; do cp -vR "./$_to" "./$_from"; done

(although this particular implementation is jank)